1. Field of the Invention
The present invention relates to computer-aided drafting systems and the like, particularly those that produce finished drawings or other accurate graphic representations from digitized input data which only roughly or approximately defines the desired final representation.
2. Description of the Prior Art
There have been numerous proposals for building automatic drafting systems of the general category just described. Many of these are referred to in an article entitled "The Instant Draftsman", published in MACHINE DESIGN, Apr. 6, 1972, pages 68-72. Still another example of such a prior system is disclosed in U.S. Pat. No. 3,720,948 issued on Mar. 13, 1973 to H. R. Eichen et al. While such prior systems may serve quite well to produce certain stylized forms of drawings such as wiring diagrams, schematics, flowcharts and structural drawings having many repetitious features which can be symbolically represented, they do not fill the need to which the present invention is particularly directed. The majority of drafting problems (such as those encountered in designing machine parts, for instance) cannot be effectively handled by a system that merely places specified symbols at arbitrarily designated locations on a diagram, or by any of the so-called "construction" methods which require that the operator start with a body of stored data that does not completely define the desired final object representation and then proceed to construct the finished drawing in a piecemeal fashion whereby the operator must intervene repeatedly to specify the dimension, locating coordinates and orientation of each individual line or other component of the drawing in turn as it is being converted from rough to finished form. The more times an operator must intervene to furnish data during the execution of the finished drawing, the less efficient and more cumbersome the drafting procedure becomes, and in an extreme case such a procedure will offer little or no advantage over manual drafting methods.